Periodic mechanism



April 15; 1958 A. w. STAFFORD P2310510 MECHANISM Filed Jan. 5, 195a 3Sheets-Sheet 1 I mm M 5:1 wax/7 74% April 15, 1958 A. w. STAFFORD2,830,456

I PERIODIC MECHANISM Filed Jan. 5. 1956 3 Sheets-Sheet 2 April 15, 1958A. w. STAFFORD. 2,830,456

PERIODIC MECHANISM Filed Jan. 5. 1956 Inwmfw 3 Sheets-Sheet 3 fllfdMaw/2% var/a) United States Patentb PERIODIC MECHANISM Alec WalterStatford, Stretford, England, assignor to T. M. M. (Research) Limited,Oldham, England The invention has reference to mechanism for impartingperiodic motion to a machine part, such mechanism being of the type inwhich the motion is derived from a rotating cam, and its object is toprovide in such mechanism means for bringing about a temporaryacceleration (with subsequent deceleration) during each stroke of theperiodically moving part.

An example of the type of mechanism to which the invention is applicableis found in the traverse mechanism of a textile spinning, twisting orwinding machine, by which the operation of building the wound materialinto a package of desired shape is achieved by the periodic movement ofthe guide by which the material is led to the winding point. In certainof such machines it is desirable during the period of reversal of thesaid guide to accelerate the motion of the guide in such manner astemporarily to alter the helix angle of the wound material, in order toassist in building a package of the desired shape, and this effect canbe attained by the use of mechanism modified as hereinafter described.

In mechanism of the said type, according to the invention, the cammotion is transmitted through the medium of a link to which periodicmotion is applied by the cooperation with the cam of one cam-follower,the character of such periodic motion being modified by the cooperationwith said cam of a second cam-follower. The effect of such modificationby the second cam-follower is to accelerate the motion of such link.

In the application of the invention to the traverse mechanism of atextile spinning, twisting or winding ma chine, .the invention may beemployed to impose -a secondary acceleration upon each stroke of thetraverse motion immediately before or after its reversal, resulting inthe required alteration of the helix angle of the ma terial which iswound upon the package during such acceleration.

A member through which the cam motion is transmitted may incorporatemountings for two cam-followers in spaced angular relationship relativeto the cam, one such cam-follower (hereinafter termed the maincam-follower) being efi'ective to traverse said member to-and-fro,whereby a push-pull connection linked to said member is actuated toproduce a main traverse motion, whilst the other cam-follower beingoperated in advance of or after the main cam-follower is caused toactuate means on said member whereby the motion of said connection ismomentarily altered just before or after its reversal by the operationof the main cam-follower.

The manner in which the invention may be carried into effect ishereinafter more fully described with reference to the accompanyingdrawings, which illustrate a form of cam-operated traverse mechanismwhich, although it can appropriately be employed in many situations inwhich the reciprocatory movement of a member is effected by theoperation of a rotary cam, has been designed for use in conjunction withthe traverse mechanism of a textile winding apparatus. In said drawings2,830,456 Patented A r. 15, 1958 Fig. l is a front elevation of the cammechanism and Fig. 2 is an end elevation thereof. Figs. 3 and 4 arefragmentary views, similar to Fig. 2, of two minor modifications, andFigs. 5 and 6 are respective front and side elevations illustratingmeans, applicable to any of the embodiments illustrated in Figs. 1 to 4,for varying the stroke of the traverse rod. Figs. 7 and 8 arediagrammatic views depicting the traverse mechanism of a textile windingmachine to which the invention may be applied.

The apparatus shown in Figs. 7 and .8 comprises a rotating shaft 10carrying a plurality of friction rollers 11, 11 upon each of which restsa tubular mandrel 12 upon which a yarn or thread is to be wound. Themandrels 12 are supported at their extremities between members (notshown) which permit the mandrels to move away from the rollers 11 inwell-known fashion as the diameter of the packages wound upon themandrels increases. Each yarn or thread, of which one is indicated at 13in Fig. 8, is delivered to the winding point by an oscillatory guide 14and the winding operation is effected by the rotation of the mandrels 12due to their frictional contact with the rollers 11.

Each guide 14 consists of an arm, having at its upper extremity a notchthrough which the yarn or thread 13 passes, and clipped to atraverse-rod 17 (as shown in Fig. 8), and the motion of saidtraverse-rod is efiected by a constantlyrotating cam 18 having aperipheral cam track 19 between the spaced walls of which is located amain cam-follower consisting of a bowl 20 carried by a block 21 mountedfor rectilinear movement upon slidebars 22 in a direction parallel tothe rotary axis of the cam 18. The arrangement is such that as the cam18 rotates it transmits a reciprocatory motion to said block 21 upon itsslide-bars 22. The cam 18 is mounted upon a shaft 23 which, togetherwith the slide-bars 22 is supported upon a base-plate 24.

The reciprocating block 21 is connected to the traverse-rod 17 by meansof a connecting rod 25 to a crank 26 fixed'to a short shaft 27 rotatablymounted in said block 21. Said shaft 27 provides a mount for the maincam-follower 20' and also an arm 28 at the free end of which is a pivotfor a bowl 29 constituting the auxiliary cam-follower, the axes of thetwo cam-follower bowls 20, 29 intersecting at the axis of the cam-shaft23. g

In the modified embodiment shown in Fig. 3, the main and auxiliarycam-followers 20, 29 are carried at the respective ends of an arm 28-1fixed at'an intermediate point in its length upon a short crank-shaft 27rotatably mounted in a slidable block 21 such as that described above.In the further modification shown in Fig. 4, the cam-follower 20 iscarried by the end of the crank-shaft 27, and the other is mounted uponan off-set 282 which is keyed on the crank-shaft 27.

In all three of the afore-described embodiments of the invention, theauxiliary cam-follower bowl follows or precedes the main cam-followerbowl 20 in the track 19 of the cam 18 by a short distance, and thearrangement is such that since the auxiliary bowl 29 reaches and passesthe reversal point 191 of the cam track 19 after or in advance of themain bowl 20, a partial rotation is imparted to the crank-shaft 27 onthe traverse block 21 near the reversal point. The elfect of suchpartial rotation of the crank-shaft 27 is to impose upon the normalmovement of the traverse rod 17 received from the sliding movement ofthe traverse block 21 a brief secondary acceleration such that, wherethe invention is applied to a textile winding machine as hereinbeforedescribed, the helix angle of the wound material is altered over a shortlength near the end of the package. When the cam-shaft 23 has rotatedthrough and the auxiliary cam-follower 29 again operates the crank-shaft27, the necessary acceleration is imposed again upon the normal'movementof the traverse-rod 17. t The axial length of thepackage over which thehelix angle is altered may be varied to suit particular requirements.This may be achieved by the use ofa variablethrow crank on the traverseblock 21, as shownin Figs. 5 and 6, where the crank-shaft 27 carries amember 261 carrying a lead-screw 262 on which is threaded a nut Said nut263 is an integral part of a stud 264 which serves as a pivot for theconnecting-rod 25. It will be seen that by rotating the screw 262, .theposition ofthe nut 263, and therefore of the pivot-stud 264 from therotary axis of the shaft 27 may be varied to adjust the stroke of thetraverse-rod 17. Alternatively, means .may be provided for adjusting theangular distance by which the two cam-followers 20, 29 are separated inrelation to the cam-shaft.

The mechanism provided by this invention may be used to off-set thedisadvantageous effect upon the formation of-a wound package of yarn orthread which may arise from defects in the package-building mechanism.For example, a delay or dwell during the reversal of the traverse, whichwould otherwise produce an accumulation of the wound material near tothe end of the package, may be countered by the means here provided fordecreasing the quantity of material wound upon the end of the package byaccelerating the traverse.

It will be understood that the foregoing references to the traversingmotion of a guide are intended to include the relative movement of sucha guide when the packagesuppor'ting spindle is subjected to an endwisetraversing motion, or when such motion is shared by the guide and thespindle. 4 7

What "Iclaim as my invention and desire to secure by Letters Patent is;

l. A mechanism of the type referred to including a rotating cam, saidcam-having a continuous cam groove, an output member, a first camfollower cooperating with said groove wherebyrsaid first cam followerreceives a reciprocatory motion, said first cam follower being connected.tosaid output member and a second cam-followeras'sociated with saidoutput member and disposed in such relation to the first cam-followerthat immediately before or after reversal of-the output member due tothe operation of the first cam-follower said output member receives asecondaryacceleration due to the operation of the second cam-follower.

2. The combination with a-rotating c-am, a cam-follower receivingreciprocatory' motion from its cooperation with assume said cam, and anoutput member partaking of said reciprocatory motion, of a secondcam-follower mounted upon- "acrank-shaft rotatably supported by'areciprocatory member associated with said first cam-follower, andarranged to cooperate with the cam before or after the firstcamfollower, whereby a part-rotary motion imparted .to said crank-shaftis effective to impose a temporary acceleration upon the output member.

3. A mechanism of the type referred to, including a link, a rotatingcam, a first cam follower associated with said cam and connected to saidlink adapted to impart periodic motion to said link, and a second camfollower associated with said cam and connected to said link adapted tomodify the motion induced in said link by said first cam follower, saidfirst mentioned cam follower being mounted on a block which is slidablein the direction of the reciprocatory movement to be imparted to thetraverse member, a shaft rotatable in said block, a crank on said shaftcarrying the second mentioned cam follower, and a second crank on saidshaft connected to said reciprocatory machine part.

4. A mechanism as claimed in claim 3, wherein the first-mentionedcam-follower is carried by an extension of the crankshaft.

5'. A mechanism 'as claimed in claim 3, wherein the two cam-followersare respectively mounted on the opposite limbs of a two-armed leverfixed to the crank-shaft.

6. A mechanism as claimed in claim 3, wherein the two cam-followers arerespectively mounted on two opposite'ly disposed cranks fixed to thecrank-shaft.

7. A mechanism as claimed in claim 3, comprising means for varying theamplitude of reciprocatory movement of the machine part.

8. A mechanism according to claim 3, comprising means for adjusting thethrow of said second crank. f

9. A mechanism according to claim 8, wherein the secondcrank is providedwith a crank-pin which is capable of adjustment longitudinally of thecrank by a lead-screw rotatably mounted therein.

10. A mechanism according to claim 8, comprising means for adjusting theangular distance separating thetwo cam-followers in relation to thecam-shaft.

11. A mechanism as claimed in claim 3, wherein the cam-followers arerotary 'bowls respectively mounted for rotation about axes whichintersect in the rotary axis of the cam.

'References Cited in the file of this patent UNITED STATES PATENTS651,828 Copland June 19, 1900 764,470 Jones July 6, 1904 1,384,344Powell July 12, 1921

